This invention relates to fuel control systems, and more particularly to fuel control systems having electronics for controlling the amount of fuel delivered to the gas turbine engine as a function of elapsed time.
Prior art turbines have attempted to design fuel control systems so that the rate of the engine acceleration closely approaches but does not reach a maximum fuel schedule line (plotted as fuel flow rate vs. speed) so that maximum acceleration of the engine can be obtained without overheating or causing damage to the engine. Prior art fuel control systems monitor various engine parameters, such as temperature, pressure, and fuel flow, controlling the fuel flow and the rate of acceleration in relation to these parameters. The problem with these prior art fuel control systems is the difficulty in obtaining accurate measurements of such parameters as the temperature, pressure and viscous drags.
The present invention overcomes these disadvantages by providing a fuel control system which electronically controls the amount of fuel flow to the engine as a function of the elapsed time from the engine start-up to deliver the optimum fuel flow to the engine.